Added rollback into the admin menu, fixed a bug where players would crash upon trying to view their own logs on relog.

core/src/io/anuke/mindustry/net/Administration.java

@@ -7,6 +7,7 @@ import com.badlogic.gdx.utils.ObjectMap;
 import com.badlogic.gdx.utils.TimeUtils;
 import io.anuke.mindustry.entities.Player;
 import io.anuke.mindustry.world.Block;
+import io.anuke.mindustry.world.Placement;
 import io.anuke.mindustry.world.blocks.types.BlockPart;
 import io.anuke.mindustry.world.blocks.types.Floor;
 import io.anuke.mindustry.world.blocks.types.Rock;
@@ -66,15 +67,61 @@ public class Administration {
     public void logEdit(int x, int y, Player player, Block block, int rotation, EditLog.EditAction action) {
     	if(block instanceof BlockPart || block instanceof Rock || block instanceof Floor || block instanceof StaticBlock) return;
     	if(editLogs.containsKey(x + y * world.width())) {
-			editLogs.get(x + y * world.width()).add(new EditLog(player, block, rotation, action));
+			editLogs.get(x + y * world.width()).add(new EditLog(player.name, block, rotation, action));
 		}
 		else {
 			Array<EditLog> logs = new Array<>();
-			logs.add(new EditLog(player, block, rotation, action));
+			logs.add(new EditLog(player.name, block, rotation, action));
 			editLogs.put(x + y * world.width(), logs);
 		}
     }
     
+    public void rollbackWorld(int rollbackTimes) {
+        for(IntMap.Entry<Array<EditLog>> editLog : editLogs.entries()) {
+            int coords = editLog.key;
+            Array<EditLog> logs = editLog.value;
+        
+            for(int i = 0; i < rollbackTimes; i++) {
+            
+                EditLog log = logs.get(logs.size - 1);
+            
+                int x = coords % world.width();
+                int y = coords / world.width();
+                Block result = log.block;
+                int rotation = log.rotation;
+            
+                if(log.action == EditLog.EditAction.PLACE) {
+                    Placement.breakBlock(x, y, false, false);
+                
+                    Packets.BreakPacket packet = new Packets.BreakPacket();
+                    packet.x = (short) x;
+                    packet.y = (short) y;
+                    packet.playerid = 0;
+                
+                    Net.send(packet, Net.SendMode.tcp);
+                }
+                else if(log.action == EditLog.EditAction.BREAK) {
+                    Placement.placeBlock(x, y, result, rotation, false, false);
+                
+                    Packets.PlacePacket packet = new Packets.PlacePacket();
+                    packet.x = (short) x;
+                    packet.y = (short) y;
+                    packet.rotation = (byte) rotation;
+                    packet.playerid = 0;
+                    packet.block = result.id;
+                
+                    Net.send(packet, Net.SendMode.tcp);
+                }
+            
+                logs.removeIndex(logs.size - 1);
+                if(logs.size == 0) {
+                    editLogs.remove(coords);
+                    break;
+                }
+            }
+        }
+    }
+    
     public boolean validateBreak(String id, String ip){
         if(!isAntiGrief() || isAdmin(id, ip)) return true;
 

core/src/io/anuke/mindustry/net/EditLog.java

@@ -4,20 +4,20 @@ import io.anuke.mindustry.entities.Player;
 import io.anuke.mindustry.world.Block;
 
 public class EditLog {
-	public Player player;
+	public String playername;
 	public Block block;
 	public int rotation;
 	public EditAction action;
 	
-	EditLog(Player player, Block block, int rotation, EditAction action) {
-		this.player = player;
+	EditLog(String playername, Block block, int rotation, EditAction action) {
+		this.playername = playername;
 		this.block = block;
 		this.rotation = rotation;
 		this.action = action;
 	}
 	
 	public String info() {
-		return String.format("Player: %s, Block: %s, Rotation: %s, Edit Action: %s", player.name, block.name(), rotation, action.toString());
+		return String.format("Player: %s, Block: %s, Rotation: %s, Edit Action: %s", playername, block.name(), rotation, action.toString());
 	}
 	
 	public enum EditAction {

core/src/io/anuke/mindustry/net/NetEvents.java

@@ -186,4 +186,11 @@ public class NetEvents {
         
         Net.send(packet, SendMode.udp);
     }
+    
+    public static void handleRollbackRequest(int rollbackTimes) {
+        RollbackRequestPacket packet = new RollbackRequestPacket();
+        packet.rollbackTimes = rollbackTimes;
+    
+        Net.send(packet, SendMode.udp);
+    }
 }

core/src/io/anuke/mindustry/net/Packets.java

@@ -153,7 +153,8 @@ public class Packets {
 			buffer.putShort((short)y);
 			buffer.putInt(editlogs.size);
 			for(EditLog value : editlogs) {
-				buffer.putInt(value.player.id);
+				buffer.put((byte)value.playername.getBytes().length);
+				buffer.put(value.playername.getBytes());
 				buffer.putInt(value.block.id);
 				buffer.put((byte) value.rotation);
 				buffer.put((byte) value.action.ordinal());
@@ -167,16 +168,34 @@ public class Packets {
 			editlogs = new Array<>();
 			int arraySize = buffer.getInt();
 			for(int a = 0; a < arraySize; a ++) {
-				int playerid = buffer.getInt();
+				byte length = buffer.get();
+				byte[] bytes = new byte[length];
+				buffer.get(bytes);
+				String name = new String(bytes);
+				
 				int blockid = buffer.getInt();
 				int rotation = buffer.get();
 				int ordinal = buffer.get();
 				
-				editlogs.add(new EditLog(Vars.playerGroup.getByID(playerid), Block.getByID(blockid), rotation, EditLog.EditAction.values()[ordinal]));
+				editlogs.add(new EditLog(name, Block.getByID(blockid), rotation, EditLog.EditAction.values()[ordinal]));
 			}
 		}
 	}
     
+    public static class RollbackRequestPacket implements Packet {
+        public int rollbackTimes;
+        
+        @Override
+        public void write(ByteBuffer buffer) {
+            buffer.putInt(rollbackTimes);
+        }
+        
+        @Override
+        public void read(ByteBuffer buffer) {
+            rollbackTimes = buffer.getInt();
+        }
+    }
+    
     public static class PositionPacket implements Packet{
         public byte[] data;
 

core/src/io/anuke/mindustry/net/Registrator.java

@@ -18,6 +18,7 @@ public class Registrator {
             BreakPacket.class,
             StateSyncPacket.class,
             BlockLogRequestPacket.class,
+            RollbackRequestPacket.class,
             BlockSyncPacket.class,
             BulletPacket.class,
             EnemyDeathPacket.class,